Israel appears poised to extend its week-long assault on Gaza by launching a ground assault, amid renewed reports last night that troops and armour were preparing to move into the besieged Palestinian territory.

As more than 300 foreign passport holders were allowed to leave Gaza after the border was temporarily opened, Israeli officials warned that a ground offensive was needed to break the military power of Hamas, which has continued to carry out rocket attacks despite pulverising air strikes.

Tank and troop reinforcements have continued to build up along the edges of the Gaza Strip with soldiers saying they are waiting for orders to go in. Israeli sources, however, stated that commando raids and temporary occupation of strategic locations were the options being considered rather than a full-scale invasion, which would involve attritional fighting in the narrow alleyways of Gaza – home to an estimated 15,000 Hamas fighters.

There have been extensive reports in the local media of Israel carrying out a land operation which had been delayed by bad weather for much of the week. However, although the Israeli government had repeatedly warned that it may launch an offensive it remained unclear whether a final decision had been taken.

All those involved, and most of those following the bloodshed in Gaza from afar, are sure who is in the right and who is in the wrong. They know who the innocent victims are and who are the wicked perpetrators. These certainties are held equally firmly by those who will be demonstrating in solidarity with the Palestinians in London today and those who plan to stage similar shows of support for Israel later this month.

Both sides see the conflict in moral terms. For supporters of the Palestinians, it could not be clearer. Israel is committing a war crime, killing people in their hundreds, hammering a besieged population from the sky (and soon perhaps on the ground too), claiming to aim only at Hamas but inevitably striking those civilians who get in the way.

Israel's cheerleaders are just as clear. Israel is the victim, hitting out now only belatedly and in self-defence. Its southern citizens have sat terrorised in bomb shelters, fearing the random rockets of Hamas, since 2005, longer than any society could tolerate without fighting back.